Beam simulation and radiation dose calculation at the Advanced Photon Source with shower, an interface program to the EGS4 code system

The interface program shower to the EGS Monte Carlo electromagnetic cascade shower simulation code system was written to facilitate the definition of complicated target and shielding geometries and to simplify the handling of input and output of data. The geometry is defined by a series of namelist commands in an input file. The input and output beam data files follow the SDDS (self-describing data set) protocol, which makes the files compatible with other physics codes that follow the same protocol. For instance, one can use the results of the cascade shower simulation as the input data for an accelerator tracking code. The shower code has also been used to calculate the bremsstrahlung component of radiation doses for possible beam loss scenarios at the Advanced Photon Source (APS) at Argonne National Laboratory